Objective To retrospectively summarize the normal reference range of trachea wall thickness,lumen diameter,wall area and wall area ratio[WA%=mean wall area/(mean wall area+lumen area)]of Chinese healthy adults,and its related factors. Also,to observe the difference of inner diameter between superior and inferior bronchus.Methods Based on computer measurement techniques of bronchus,a CT quantitative analysis was carried out in 701 cases of normal healthy people who had negative results in lung cancer screening of health examination at our hospital.Results The value of trachea wall thickness,lumen diameter,wall area and wall area ratio was(1.322 mm,18.024 mm,78.93 mm2 ,0.27)respectively.In different gender,the trachea wall thickness,lumen diameter,wall area and wall area ratio had statistical significance (P<0.05).Also,they had good consistency with gender (r=-0.512,-0.472,-0.559,0.315).In different gender and age,the difference of inner diameter between the superior bronchus and inferior bronchus was always a positive value.Conclusion The CT quantitative analysis method has advantages of convenience,direct-vie-wing and accuracy.It is good for quantitative detection and research of bronchus structure.Bronchial wall thickness,lumen diameter, wall area and wall area ratio have significant difference because of gender.The inner diameter of superior bronchus is always greater than that of the inferior bronchus.

Objective: To explore the differences among three methods of nucleic acid extraction and three kinds of real-time fluorescence quantitative PCR instrument. Methods: Twenty-five respiratory virus nucleic acid and 25 enterovirus nucleic acid positive samples were with selected at random and nucleic acids were extracted by using three methods (method A, B, and C). The results among different methods were analyzed by randomized block design. 25 respiratory viral nucleic acid positive specimens and enterovirus nucleic acid positive samples were detected by using three kinds of real-time fluorescence quantitative PCR instrument (instrument A, B, and C). The results among different instruments were analyzed by randomized block design. Results: There was a significant difference among three methods of nucleic acid extraction in results(χ²=42.9162, P<0.001), in which method A and C had not significant difference(Z=0.837, P=0.3816>0.05), while method A vs. B, B vs. C were significantly different(Z=7.025, P<0.001; Z=7.9, P<0.001). There was also a significant difference among three kinds of real-time fluorescence quantitative PCR instrument in results(χ²=23.773, P<0.001), in which instrument B and C had no significant difference(Z=0.75, P=0.4533>0.05), while instrument A vs. B, A vs. C were significantly different(Z=5.70, P<0.001; Z=6.45, P<0.001). Conclusions There is difference among different methods and instruments in the test results under the same condition, which call for options in practical work according to need.